1. Field of the Invention
The present invention is related to a tool holder of the type having a recess into which a cutting insert is removably secured by means of a locking pin which extends through the cutting insert and into the tool holder.
The present invention is also related to the locking pin for use with such a tool holder.
2. Description of the Prior Art
Presently, it is known to use a clamping pin to hold a cutting insert in place relative to a recess provided in a tool holder. For example, one known apparatus is described in U.S. Pat. No. 3,490,117 to Hertel. The tool holder described in this patent includes a clamping pin which must be removed from the holder in order to index or remove the cutting insert from the holder. Such an operation is time consuming and involves the existence of a loose part which could be lost or inadvertently discarded during the changing of a cutting insert. It is an object of this invention to provide a tool holder wherein the cutting tool can be indexed or replaced without removal of the locking or clamping pin. The clamping pin described in Hertel includes a thickened head which bears against a countersunk portion of the bore wall extending through the cutting insert to hold the insert in place. However, the compressive forces exerted by the thickened head against the insert are not specifically identified as providing specific orientation relative to the tool holder surfaces against which the cutting insert is to be held. It is a further object of this invention to provide a tool holder wherein the locking pin includes means to positively press the cutting insert against at least two surfaces of the tool holder recess. In particular, the locking pin will positively press the cutting insert downward into the recess and simultaneously positively press the cutting insert backward into the recess, the downward pressure being near the front of the recess to provide the greatest moment of force to prevent the cutting insert from lifting from the recess. Another object of this invention includes providing a tool holder having the foregoing objects and wherein the locking pin does not project above the outer face of the insert. Yet a further object of this invention is to provide a tool holder of the type described herein requiring a minimum amount of movement to lock the cutting insert in place. It is also an object to provide a locking pin useful in accomplishing the objects described above wherein the pin can be used with standard cutting inserts used in operations such as threading, grooving, turning and boring.